If having the correct number of copies of each chromosome is so important, how is it possible that both female (with two copies of the X chromosome per cell) and male (with only one copy of the X chromosome per cell) individuals are phenotypically normal?

Which conditions are necessary for natural selection to occur? select all of the answers that apply. a. inheritable adaptations vary among individuals. b. the population size is increasing. c. more individuals are born than can survive. d. fitness varies among individuals. e. the environment changes suddenly and drastically.

Which muscle cell structure stores calcium ions that are used to trigger the contraction?

Which individual would be the safest from a lightening strike? a. a person standing 8 miles away b. a person on a bike 8 miles away c. a person in a tent 8 miles away d. a person in a house 8 miles away select the best answer from the choices provided a b c d